Ferrocarril de Antofagasta a Bolivia

The railway started at the Chilean port of Antofagasta. It proceeded up the front range of the Andes to Ollagüe on the Bolivian border, requiring a notable piece of civil engineering, the Loa viaduct. However, in 1914 the line was rerouted upstream of the Conchi reservoir and trains no longer ran across the viaduct. Across the Bolivian pampas the lined reached Uyuni and Oruro. At Oruro, the gauge changed to 1,000 mm (3 ft 3+3⁄8 in) metre gauge for the remainder of the route to La Paz, the capital of Bolivia. A number of branches were added to reach various mining fields. The Collahuasi mine branch from Ollagüe reached 4,815 m (15,797 ft) above sea level, regarded at the time of construction as the highest railway in the world. The total length of the 2 ft 6 in (762 mm) gauge lines, including branches and subsidiaries, was 1,537 km (955 mi).

In Bolivia there had been proposals in the 1860s and early 1870s to establish a Boliva's first railway to the ports of the Pacific through the Peruvian por of Arica.^[1] A series of disputes with Peru shifted the focus of the railway to have it reach the ocean farther south through the Bolivan coastal department.^[1] The railway was expected to have great impact for the development of Bolivia increasing the state's income, integrating the peripheral coastal province, cheapen transport to coast and providing external trade that did not depend on third party.^[1] The Bolivian parliament originally rejected the plan since they favoured development of La Paz and Cochabamba in the north, the connection of these cities to the Peruvian ports and to maintain these regions as supply bases for southwestern Bolivia.^[1] Opposition by Compañía Minera Huanchaca's Chilean investors –who never controlled more than 1⁄5 of the company– was also a factor according to Guillermo Billinghurst. In Billinghurst's view Chilean interest were worried about an Litoral Department becoming increasingly Bolivian but then turned in favour of the railway once Chile took control of the region in 1879.^[1]

The history of the railway dates back to 1872 with the grant of a concession by the government of Bolivia to Melbourne Clarke & Co, the territory around Antofagasta being part of Bolivia at this date. The railway was organised as the Antofagasta Nitrate & Railway Company. Construction started in 1873, with the first section opening late in that year, motive power provided by mules. Steam locomotives were introduced in 1876, and by 1879 the railway had extended about 150 km (93.2 mi) into the interior.^{[citation needed]}

War broke out in 1879 between Chile on one side, and Peru and Bolivia on the other. One of the causes of the war was an attempt by the Bolivian government to levy back taxes on the railway. The War of the Pacific ended in 1883, and Chile gained the region around Antofagasta as well as part of Peru.

Control of the railway passed to the Company Huanchaca of Bolivia in 1887, who subsequently floated the railway on the London stock exchange in 1888 as the FCAB. The Huanchilaca company retained the right to operate the railway for a further 15 years. The line reached Oruro in Bolivia, the end of the 2 ft 6 in (762 mm) section, in 1892, and branches continued to be added over subsequent years.

British business interests resumed control of the entire system in 1903.^{[citation needed]} Traffic reached a point where the port of Antofagasta was unable to cope. A new port was opened to the north at Mejillones in 1906, together with a new line bypassing Antofagasta.^{[citation needed]} In 1909 the FCAB purchased the FC Caleta Coloso a Aguas Blancas, a railway operating in the mineral-rich desert regions south of Antofagasta.^{[citation needed]} Although also of 2 ft 6 in (762 mm) gauge, the FCCCAB was never integrated into the FCAB, and always operated as a separate entity.

The entire region is a desert, with almost no rainfall. The company constructed a system of pipes and reservoirs to bring water for the railway from the high Andes, eventually becoming responsible for supplying Antofagasta with water as well.

Bolivian government interests supported the construction of a railway between Oruro and the Bolivian capital, La Paz, and this line was opened in stages between 1908 and 1913.^{[citation needed]} This line was constructed to metre gauge, and was leased to the FCAB. The FCAB now had two operating divisions, one using 2 ft 6 in (762 mm) gauge, the other 1,000 mm (3 ft 3+3⁄8 in) metre gauge.

Primary traffic on the railway has always been mineral, first with nitrate (an essential ingredient of explosives prior to World War I) and as of 2020 copper being very important. Sulphuric acid is transported uphill and copper comes down. The railway also transported concentrates of other minerals and lithium brine.^[3] Traffic between Bolivia and northern Chile grew in importance and continues to this day.

Passengers were catered for in earlier days by a luxury train with sleeping and dining carriages, one of the few trains on 2 ft 6 in (762 mm) gauge anywhere in the world with these conveniences. The International, as the train was called, continued to operate on the metre gauge after gauge conversion. The train was later replaced by railcars, however no passenger service is provided today except south of Oruro with the Wari Wari del Sur running several times a week and serving several stations en route.

• Arica–La Paz railway
• FC Caleta Coloso a Aguas Blancas
• Salta–Antofagasta railway
• Tocopilla railway
• Rail transport in Chile
• Rail transport in Bolivia